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1.
J Biol Regul Homeost Agents ; 34(6): 2003-2015, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33325224

RESUMEN

This study investigated the tolerance and safety of pasteurized donor human milk (PDHM) given either alone or together with commercially-used supplements in a porcine model of premature infants. A porcine model, mimicking human neonates at 30-32 weeks of gestational age, was used. The 7-day experiment was performed on 20 piglets. After birth, the piglets were infused with porcine immunoglobulins via the umbilical artery and surgically fitted with a stomach port. The piglets were then randomized into five groups and fed either PDHM, different variants of fortified PDHM or 'raw' human milk (RHM). Preterm piglets fed PDHM showed signs of gastrointestinal intolerance. Four piglets across the various PDHM-fed groups died, none of them were from the group fed PDHM supplemented with long-chain polyunsaturated fatty acids (LC PUFA). In all groups fed PDHM, macroscopic features of enterocolitis were observed, however, these pathological gut changes were less manifested in piglets receiving PDHM supplemented with LC PUFA. The piglets fed RHM had no specific signs of gut damage. The poor tolerance to PDHM suggests changes in milk composition caused by the Holder pasteurization. The supplementation with LC PUFA probably improves tolerance to PDHM.


Asunto(s)
Recien Nacido Prematuro , Leche Humana , Animales , Edad Gestacional , Humanos , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Modelos Animales , Pasteurización , Porcinos , Donantes de Tejidos
2.
Animal ; 14(10): 2129-2137, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32398171

RESUMEN

Obestatin is a gastrointestinal peptide having wide-ranging effects on cell proliferation; however, its mechanism of action remains poorly understood. Thus, the aim of the study was to elucidate the effect of exogenous obestatin on the postnatal structural development of the small intestine. Seven-day-old piglets with an average BW of 1.56 ± 0.23 kg were divided into four groups (n = 10) that received intragastrically obestatin (2, 10 or 15 µg/kg BW) or vehicle. After a 6-day experimental period, morphological analysis of gastrointestinal tract and small intestine wall (mitosis and apoptosis indexes, histomorphometry of mucosa and muscularis layers) was performed. The study revealed a seemingly incoherent pattern of the histological structure of the small intestine among the experimental groups, suggesting that the effect of obestatin is both intestinal segment specific and dose dependent. Histomorphometric analysis of the small intestine showed that higher doses of obestatin seem to promote the structural development of the duodenum while simultaneously hindering the maturation of more distal parts of the intestine. Intragastric administration of obestatin increased the crypt mitotic index in all segments of the small intestine with the strongest pro-mitotic activity following the administration of obestatin at a dose of 10 and 15 µg/kg BW. The significant differences in the number of apoptotic cells in the intestinal villi among the groups were observed only in proximal jejunum and ileum. In conclusion, it seems that obestatin shows a broad-spectrum of activity in the gastrointestinal tract of newborn piglets, being able to accelerate its structural development. However, the varied effect depending on the intestinal segment or the concentration of exogenous obestatin causes that further research is needed to clarify the exact mechanism of this phenomenon.


Asunto(s)
Ghrelina , Intestino Delgado , Porcinos/crecimiento & desarrollo , Animales , Animales Recién Nacidos , Duodeno , Mucosa Intestinal , Yeyuno
3.
Food Chem Toxicol ; 125: 78-84, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30553875

RESUMEN

BACKGROUND: The intestinal tract is important for development of immune tolerance and disturbances are suggested to trigger autoimmune disorders. The aim of this study was to explore the effect of Maillard products in skim milk powder obtained after long storage, compared to fresh skim milk powder. METHODS: Young rats were weaned onto a diet based on skim milk powder with high concentration of Maillard products (HM-SM, n = 18) or low (C-SM, n = 18) for one week or four weeks. Weekly body weight and feed consumption were noted. At the end, organ weights, intestinal histology, permeability and inflammatory cytokines were evaluated. RESULTS: Rats fed with HM-SM had after one week, 15% less weight gain than controls, despite equal feed intake. After one week thymus and spleen were smaller, intestinal mucosa thickness was increased and acute inflammatory cytokines (IL-17, IL-1ß, MCP-1) were elevated. After four weeks, cytokines associated with chronic intestinal inflammation (fractalkine, IP-10, leptin, LIX, MIP-2, RANTES and VEGF) were increased in rats fed with HM-SM compared to C-SM. CONCLUSION: High content of Maillard products in stored milk powder caused an intestinal inflammation. Whether this is relevant for tolerance development and future autoimmune diseases remains to be explored.


Asunto(s)
Enteritis/inducido químicamente , Reacción de Maillard , Leche , Aumento de Peso , Animales , Citocinas/farmacología , Mediadores de Inflamación/farmacología , Tamaño de los Órganos , Polvos , Ratas
4.
J Biol Regul Homeost Agents ; 31(1): 87-92, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28337875

RESUMEN

Preterm human neonates, contrary to preterm piglets, obtain immunoglobulins from their mothers via the placenta during intrauterine development. However, one should note that the majority of trans-placental transfer of immunoglobulins in humans takes place during the last trimester of pregnancy. It is also known that the feeding of limited amounts of colostrum or systemic infusion of small amounts of serum improves the survival of preterm and full-term piglets. Full-term piglets deprived of their mother's immunoglobulins exhibit strong apathy and develop watery diarrhoea, often resulting in death. The aim of the current study was to determine if provision of immunoglobulins using different approaches would be beneficial for survival outcomes. To reach the immunological sufficient level we infused immunoglobulins intravenously in amount mimicking the blood level in piglets fed with sow colostrum. Intravenous infusion of immunoglobulins in both preterm and full-term newborn piglets fully ensured their survival, growth and blood immunoglobulin G and protein levels similar to those observed in piglets fed colostrum. Piglets completely deprived of immunoglobulins exhibited significantly lower blood levels of immunoglobulins and protein compared to colostrum-fed animals. Piglets infused with only serum exhibited significantly lower blood immunoglobulin G level compared to those infused with immunoglobulins. In conclusion, based on the data obtained, we suggest that passive immune support provided by colostrum intake or early systemic infusion of Ig's in sufficient amounts is key to ensuring the general well-being of preterm and full-term new born piglets, used as an animal model for the human infant.


Asunto(s)
Alimentación Animal/análisis , Calostro/inmunología , Suplementos Dietéticos/análisis , Inmunoglobulinas/administración & dosificación , Recien Nacido Prematuro/inmunología , Porcinos/inmunología , Animales , Animales Recién Nacidos , Calostro/química , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro/crecimiento & desarrollo , Modelos Animales , Embarazo , Porcinos/crecimiento & desarrollo
5.
Gen Comp Endocrinol ; 248: 69-78, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28212895

RESUMEN

This study investigated the effect of enteral administration of obestatin on the contractility of whole-thickness preparations of duodenum and middle jejunum, as well as on the morphology of the enteric nervous system (ENS). Suckling rats were assigned to 3 groups (n=12) treated with: C-saline solution; LO-obestatin (125nmol/kgb.wt); HO-obestatin (250nmol/kgb.wt). Saline solution or obestatin were administered twice daily, from the 14th to the 21st day of life. Sections were studied in an organ bath, for isometric recording in the presence of acetylocholine (ACh), atropine (ATR) and tetradotoxin (TTX). Thickness of intestinal muscularis layer, the number of interstitial cells of Cajal (ICC) were measured in the paraffin sections. The immunodetection of Muscarinic Acetylocholine Receptor 2 (M2 receptor) was performed in the intestinal segments. In both intestinal segments HO treatment decreased the amplitude of spontaneous contraction compared to that observed in the C group. In the middle jejunum, the LO treatment also decreased the amplitude. TTX and ATR had no effect on amplitude of spontaneous contraction in the jejunum of LO and HO-treated animals. Compared to the C group, duodenal sections from HO animals and middle jejunum sections from LO and HO groups displayed a lower amplitude in response to ACh and EFS evoked contraction. An increase in the thickness of the muscularis layer was observed in the duodenum of LO and HO groups whereas the number ICC did not change significantly after treatment with obestatin. Moreover, the enteral administration of obestatin did not effect significantly on the cytoplasmic expression of M2 receptor in the jejunum. Our study demonstrated that enteral administration of obestatin to suckling rats influences small intestine contractility in the segment specific manner.


Asunto(s)
Motilidad Gastrointestinal/fisiología , Ghrelina/administración & dosificación , Ghrelina/farmacología , Intestinos/fisiología , Contracción Muscular/efectos de los fármacos , Acetilcolina/farmacología , Animales , Recuento de Células , Estimulación Eléctrica , Nutrición Enteral , Femenino , Motilidad Gastrointestinal/efectos de los fármacos , Células Intersticiales de Cajal/citología , Células Intersticiales de Cajal/efectos de los fármacos , Intestinos/efectos de los fármacos , Masculino , Proteínas Proto-Oncogénicas c-kit/metabolismo , Ratas , Receptor Muscarínico M2 , Tetrodotoxina/farmacología
6.
J Physiol Pharmacol ; 68(5): 693-698, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29375043

RESUMEN

Ghrelin and obestatin are gastrointestinal peptides with a potential role in the programming of metabolism in newborns. The present study aimed to investigate the influence of preterm delivery on ghrelin and obestatin concentrations in the maternal blood plasma and breast milk as well as their gene expressions in the mammary epithelial cells (MECs). On the 3rd day after delivery, milk and plasma samples were collected from mothers that carried to term or gave birth prematurely (< 36 weeks of gestation) and analyzed for ghrelin and obestatin concentrations. MECs isolated from the milk were analyzed for the relative expression of GHRL splice variants. In both groups ghrelin concentrations were significantly lower in milk than in blood plasma. In the preterm group obestatin concentrations were significantly higher in milk than in blood plasma but significantly lower in comparison to that of the control mothers. The expression of GHRL mRNAs was higher (P < 0.05) in MECs isolated from the preterm group as compared to those isolated from control mothers. The concentration of obestatin (but not ghrelin) in the breast milk is dependent on the term of pregnancy. Moreover, the lactating mammary gland is one of the sources of ghrelin and obestatin.


Asunto(s)
Células Epiteliales/metabolismo , Ghrelina/biosíntesis , Glándulas Mamarias Humanas/metabolismo , Leche Humana/metabolismo , Nacimiento Prematuro/metabolismo , Adulto , Biomarcadores/sangre , Biomarcadores/metabolismo , Femenino , Humanos , Embarazo
7.
J Physiol Pharmacol ; 67(4): 543-553, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27779475

RESUMEN

This study investigated the effect of a high-fat (HF) diet on plasma adiponectin and steroid hormones levels, and the protein expression of adiponectin and its receptors, in the gonads and gonadal (periovarian and epididymal) white adipose tissue (WAT) of dams and their offspring. Female Wistar rats were fed a HF diet (30% fat) or a standard breeding (BD) diet (5% fat) during pregnancy and lactation. At 21 days of lactation, mothers and both sexes of prepubertal offspring were killed by decapitation. Plasma adiponectin, testosterone (T) and oestradiol (E2) levels were analyzed by ELISA. The protein expression of adiponectin and its receptors 1 (AdipoR1) and 2 (AdipoR2) was assayed by Western blot and immunohistochemistry. Plasma adiponectin levels in HF dams were lower compared to BD dams, and correlated with protein expression of adiponectin and its receptors, but not with steroid hormone levels. Female HF offspring had lower plasma adiponectin levels, reduced intensity of adiponectin and AdipoR1 in the ovary, and decreased E2 in parallel with increased T. In contrast, male HF offspring had higher plasma adiponectin levels, increased intensity of adiponectin and AdipoR1 in the testis, and decreased T in parallel with increased E2. In conclusion, feeding a HF diet to dams during pregnancy and lactation disturbs plasma adiponectin levels and protein expression, both in female and male offspring; it lowers adiponectin secretion and protein expression in the female whereas in male it is increased. As a consequence, there is disruption of steroid secretion in offspring, towards T in females, and E2 in males.


Asunto(s)
Adiponectina/metabolismo , Dieta Alta en Grasa , Efectos Tardíos de la Exposición Prenatal , Adiponectina/sangre , Animales , Estradiol/sangre , Femenino , Lactancia , Masculino , Fenómenos Fisiologicos Nutricionales Maternos , Ovario/metabolismo , Embarazo , Ratas Wistar , Receptores de Adiponectina/metabolismo , Caracteres Sexuales , Testículo/metabolismo , Testosterona/sangre
8.
Gen Comp Endocrinol ; 208: 109-15, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25193331

RESUMEN

Obestatin is a 23-amino acid peptide encoded by the ghrelin gene. We have investigated the effect of obestatin on intestinal contractility in rats ranging from the suckling period till adolescence. Duodenal and middle jejunum whole-thickness preparations from neonatal and adult rats were studied in an organ bath, for isometric recording under treatment with obestatin (1µmolL(-1)) in the presence of acetylocholine (ACh), atropine and tetradotoxin (TTX). Both the EFS and ACh-stimulated contractile response, as well as spontaneous contractile activity is age-dependent and specific for the segment of jejunum. Except for the middle jejunum of 7day old rats, treatment with obestatin caused a significant TTX-sensitive increase in the amplitude of EFS-stimulated off-contraction of both intestinal segments studied. Following injection of obestatin, the amplitude of spontaneous contraction in the duodenum increased in 7day old rats. In the middle jejunum, treatment with obestatin significantly increased both the amplitude and frequency of spontaneous contraction in rats till the 28th day of life, whereas in adult rats the observed effect of obestatin was the opposite (P<0.001 and P<0.0001, respectively). The effects of treatment with obestatin on stimulation with increasing doses of ACh were only observed in the preparations from suckling rats. ACh-stimulated contractility in the duodenum was decreased while in the middle jejunum the observed effect was opposite. These results indicate the importance of peripheral obestatin in the cholinergic control of intestinal contractility in both neonatal and adult rats.


Asunto(s)
Envejecimiento/fisiología , Ghrelina/farmacología , Intestinos/fisiología , Contracción Muscular/efectos de los fármacos , Acetilcolina/farmacología , Animales , Duodeno/efectos de los fármacos , Duodeno/fisiología , Estimulación Eléctrica , Técnicas In Vitro , Intestinos/efectos de los fármacos , Yeyuno/efectos de los fármacos , Yeyuno/fisiología , Masculino , Ratas Wistar
9.
Domest Anim Endocrinol ; 46: 12-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24135555

RESUMEN

Leptin has been shown to play an integral role in the endocrine regulation of metabolism. Moreover, a substantial amount of this peptide has been found in colostrum and milk. The aim of the study was to investigate the effects of exogenous leptin, administered intragastrically, on the process of autophagy and the changes in cell hyperplasia and hypertrophy in the small intestine mucosa. Three groups (n = 6) of neonatal piglets were used in the study. The pigs were fed either by their sows (sow-reared piglets) or with only milk formula, or with milk formula together with leptin administered via a stomach tube (10 µg/kg BW) every 8 h for 6 d. We have shown that pure milk formula feeding significantly elevates (P < 0.05) autophagy compared with that observed in sow-reared piglets. Compared with the control group, feeding milk formula supplemented with leptin resulted in a significant decrease (P < 0.05) in immunodetection of microtubule-associated protein 1 light chain 3, as well as significantly accelerated epithelial cell renewal (P < 0.05). We demonstrated that autophagy is involved in the remodeling of the small intestine mucosa and that leptin, when administered enterally, may be an important factor for its regulation.


Asunto(s)
Autofagia/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Intestino Delgado/efectos de los fármacos , Leptina/administración & dosificación , Porcinos/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Animales Recién Nacidos , Animales Lactantes , Autofagia/fisiología , Peso Corporal/efectos de los fármacos , Peso Corporal/fisiología , Células Epiteliales , Femenino , Inmunohistoquímica/veterinaria , Etiquetado Corte-Fin in Situ/veterinaria , Mucosa Intestinal/citología , Mucosa Intestinal/metabolismo , Intestino Delgado/citología , Intestino Delgado/metabolismo , Leptina/metabolismo , Microscopía Confocal/veterinaria , Proteínas Asociadas a Microtúbulos/metabolismo , Distribución Aleatoria , Estadísticas no Paramétricas
10.
J Anim Sci ; 90 Suppl 4: 311-4, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23365364

RESUMEN

Use of nutritional components from the milk and eventually from the solid feed relates to the growth and development of gastrointestinal tract (GIT). We studied the effect of pancreatic-like enzymes [porcine pancreatic enzymes (Creon) or microbial-derived amylase, protease, and lipase] on GIT morphology and lipid absorption in suckling piglets. Both enzyme preparations, in low or high dose, were fed via a stomach tube twice a day for 7 d starting at 8 d of age and controls received vehicle, n = 6. The day after treatments ended, lipid absorption was tested after which pigs were euthanized and GIT was examined. Enzyme cocktails, irrespective of their origin, increased (P < 0.001) triglyceride level in blood. Enzyme preparation affected (P < 0.001) small intestinal mucosal thickness, villi length, and crypt depth and (P < 0.01) mitotic division of enterocytes. In addition, the external administration of pancreatic enzymes stimulated pancreatic growth as observed by increased (P < 0.05) mitotic division of pancreatic cells. The study revealed that pancreatic or pancreatic-like enzymes of microbial origin administrated in the early postperinatal period enhance GIT development and may be used to better prepare the GIT of piglets for milk use and weaning.


Asunto(s)
Amilasas/farmacología , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/crecimiento & desarrollo , Pancrelipasa/farmacología , Péptido Hidrolasas/farmacología , Porcinos/crecimiento & desarrollo , Amilasas/metabolismo , Animales , Tracto Gastrointestinal/anatomía & histología , Metabolismo de los Lípidos , Péptido Hidrolasas/metabolismo
11.
J Anim Sci ; 90 Suppl 4: 327-30, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23365369

RESUMEN

Colostrum is an indispensable source of antibodies (IgG) protecting the newborn pig against infection. We studied the effect of feeding colostrum and purified IgG on early structure and development of the gastrointestinal tract (GIT). Newborn littermate pigs were fed either colostrum, an elemental diet (ED), or an ED supplemented with purified serum IgG (ED + IgG) for 24 h or then only ED up to 72 h. Afterwards, pigs were slaughtered. Colostrum-fed pigs or ED supplemented with IgG (ED + IgG) increased thickness (P < 0.001) of stomach mucosa and muscularis (P < 0.05) compared to the ED group not receiving IgG. Feeding an ED supplemented with IgG improved morphology of the GIT towards that of colostrum-fed piglets and indicates a beneficial effect of IgG on GIT development in neonatal pigs. Immunohistochemical studies indicate that ED feeding may influence the expression of nitric oxide synthase in jejunal myenteric (but not submucous) neurons of newborn pigs.


Asunto(s)
Alimentación Animal/análisis , Calostro , Dieta/veterinaria , Tracto Gastrointestinal/anatomía & histología , Inmunoglobulina G/farmacología , Porcinos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Sistema Nervioso Entérico/efectos de los fármacos , Sistema Nervioso Entérico/enzimología , Sistema Nervioso Entérico/fisiología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa/metabolismo
12.
J Dairy Sci ; 92(3): 1038-49, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19233797

RESUMEN

In milk-fed calves, the effects of sodium-butyrate (Na-butyrate) to replace flavomycin on growth performance and some mechanisms involved were studied. Pancreatic and intestinal morphology, digestive enzyme activities, plasma gut regulatory peptide concentrations, and expression of their receptors in the gastrointestinal tract were measured. Gastrointestinal tract defense systems were examined by measuring protein levels of 2 heat-shock proteins (HSP27 and HSP70). The calves were randomly allocated into 2 groups fed the same basic diet with flavomycin as an antimicrobial growth promoter or with Na-butyrate (3 g/kg of dry matter). Sodium-butyrate disappeared quickly in the upper gut and was not found in circulating blood. Supplementation with Na-butyrate enhanced growth rate and improved feed conversion into body weight gain compared with the flavomycin group. Supplementation with Na-butyrate was likely associated with an improvement in efficacy of the gastrointestinal tract digestive capacities expressed by enhanced production of digestive enzymes and increased absorptive capacities in the upper small intestine. The effects could have been controlled by insulin-like growth factor-1 but probably not by any of the cholecystokinin/gastrin peptide family. Concentrations of HSP27 and HSP70 were increased in stomach and colon of calves receiving Na-butyrate, thereby assuring protection of cells with intensive metabolism (chaperone function). In conclusion, beneficial effects of Na-butyrate on maturation of gastrointestinal functions were shown in milk-fed calves and may be applied to young mammals of other species.


Asunto(s)
Butiratos/farmacología , Bovinos/crecimiento & desarrollo , Tracto Gastrointestinal/efectos de los fármacos , Sustancias de Crecimiento/farmacología , Crecimiento y Desarrollo/efectos de los fármacos , Sustitutos de la Leche , Animales , Antibacterianos/farmacología , Bambermicinas/farmacología , ADN/análisis , Tracto Gastrointestinal/crecimiento & desarrollo , Tracto Gastrointestinal/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Mucosa Intestinal/química , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/enzimología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Páncreas/efectos de los fármacos , Páncreas/enzimología , Proteínas/análisis , Distribución Aleatoria , Receptores de Colecistoquinina
13.
J Anim Sci ; 86(11): 2952-61, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18502885

RESUMEN

The aim of the study was to investigate the effects of supplementation of a microencapsulated blend of tributyrin and lactitol (TL) to a standard European (EU) diet without antibiotic growth promoters on intestinal metabolism and mucosa development of weaned piglets and to compare it with a standard US diet containing animal proteins, zinc oxide, copper sulfate, and carbadox. Ninety piglets weaned at 21 d were divided into 3 dietary groups consisting of 5 replicates each: 1) US diet supplemented with 55 mg/kg of carbadox, and 2.5% each of plasma proteins and spray-dried blood cells in the first phase, 3,055 mg/kg of Zn in the first and second phases, and 180 mg/kg of Cu in the third phase; 2) EU diet based on vegetable proteins and no antibiotics; and 3) the same EU diet supplemented with 3,000 mg/kg of microencapsulated TL. The study was divided into 3 phases: 0 to 7, 8 to 21, and 22 to 35 d. On d 7, 21, and 35, animals were weighed, and feed consumption and efficiency were determined. On d 14 and 35, one pig per pen was killed, and the intestinal contents and mucosa from the proximal, middle, distal jejunum and the ileum were sampled. Intestinal wall sections were fixed for histological analysis, and intestinal content was used for VFA, ammonia, and polyamine analysis. Throughout the study (d 0 to 35), the US diet had greater ADG and ADFI than the EU diet (P < 0.05). The EU diet supplemented with TL tended to have 11% greater ADG (P = 0.17). Feeding the EU diet caused a reduction in proximal and middle jejunum villi length by 10% (P < 0.05) and an increase in crypt size in proximal jejunum (P < 0.05) compared with the US diet, probably due to an increased rate of cell loss and crypt cell production. The TL supplementation resulted in longer villi along the jejunum and less deep crypts in the proximal jejunum (+15.9 and -8.9%, respectively; P < 0.05) than the unsupplemented EU diet. The TL diet increased the concentrations of cadaverine and putrescine in the small intestine (P < 0.05) and seemed to increase cadaverine, histamine, putrescine, and spermine in the large intestine by 1.5- to 10-fold compared with the US or EU diet. In conclusion, although the US diet had a greater effect on growth performance and mucosal trophic status than the EU diets, the supplementation with slowly released TL seemed to be an effective tool to partially overcome the adverse effects of vegetable protein diets.


Asunto(s)
Dieta/veterinaria , Suplementos Dietéticos , Mucosa Intestinal/metabolismo , Alcoholes del Azúcar/administración & dosificación , Porcinos/fisiología , Triglicéridos/administración & dosificación , Aminas/metabolismo , Amoníaco/metabolismo , Animales , Europa (Continente) , Ácidos Grasos Volátiles/metabolismo , Femenino , Mucosa Intestinal/anatomía & histología , Intestinos/anatomía & histología , Yeyuno/anatomía & histología , Masculino , Distribución Aleatoria , Porcinos/crecimiento & desarrollo , Porcinos/metabolismo , Estados Unidos , Destete
14.
Micron ; 39(8): 1363-70, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18337110

RESUMEN

The biocompatibility of titanium implants in bone depends on the response shown by cells in contact with the implant surface. Several developments have been targeted at achieving successful implant treatment. The aim of this study was to develop a novel preparation procedure to evaluate the bone cell response produced at the bone-implant interface using the technique scanning electron microscopy with backscattered electron imaging (SEM-BSE). Dental prostheses with an SLA-modified or TOP-modified surface were implanted in a toothless part of the mandibula in female pigs. The animals were sacrificed 12 weeks after surgery, at which time block specimens containing the implants were obtained. These specimens were then processed for SEM-BSE by optimizing a protocol involving chemical fixation and heavy metal staining. In addition, element distribution maps for the implant-bone tissue interface were obtained using a microanalytical system based on energy-dispersive X-ray spectrometry (EDS). This novel visualisation approach enabled a comprehensive study of the extracellular matrix and cell components of the host tissues neoformed around the implant. SEM-BSE images also provided ultrastructural details of the bone cells. This technique appears to be an effective and very promising tool for detailed studies on the implant-bone tissue interface and the host response to the bone incorporation process.


Asunto(s)
Huesos/ultraestructura , Implantes Dentales , Oseointegración , Animales , Microanálisis por Sonda Electrónica , Femenino , Microscopía Electrónica de Rastreo , Porcinos , Titanio
15.
J Anim Sci ; 85(2): 404-12, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17235025

RESUMEN

The objective of this study was to quantify and compare the effects of sow's milk and 2 milk replacer diets (containing clotting or non-clotting protein sources) on exocrine pancreatic secretion, plasma cholecystokinin, and immunoreactive cationic trypsin in pigs. In addition, the relationship between exocrine pancreatic secretion and growth in milk-fed pigs was studied. In a changeover experiment, 9 chronically catheterized pigs of 6.6 +/- 0.19 kg of BW were studied for 3 wk. Pigs were assigned to each of 3 diets. Exocrine pancreatic secretion was measured from the third to the seventh day on each diet. The protein content and trypsin activity of the pancreatic juice were measured. Blood samples were taken at 10 min before and after milk ingestion and were analyzed for cholecystokinin and immunoreactive cationic trypsin. Pancreatic protein and trypsin secretion did not differ between pigs fed sow's milk and those fed milk replacer, but the volume secreted was less for the pigs fed sow's milk (0.75 vs. 1.03 mL x kg(-1) x h(-1); P < 0.01). A postprandial response to milk intake was not observed. The 2 milk replacer diets did not affect exocrine pancreatic secretion differently. The average exocrine pancreatic secretion (volume, 0.94 mL x kg(-1) x h(-1); protein, 4.28 mg x kg(-1) x h(-1); trypsin, 1.65 U x kg(-1) x h(-1)) was intermediate between literature values for suckling and weaned pigs. Plasma cholecystokinin was elevated (approximately 18 pmol x L(-1)) and showed low correlations with the pancreatic secretion traits. Plasma immunoreactive cationic trypsin was not significantly related to any of the pancreatic secretion traits and should therefore not be used as an indicator for exocrine pancreatic function in milk-fed pigs. Exocrine pancreatic secretion varied substantially among individual pigs (protein, 0.22 to 13.98 mg x kg(-1) x h(-1)). Pancreatic protein and trypsin secretion showed a positive, nonlinear relationship with performance traits. It was concluded that neither specific sow's milk ingredients nor the protein source are responsible for a low pancreatic protein secretion in suckling pigs. Exocrine pancreatic secretion was positively correlated with ADG in pigs at an identical milk intake.


Asunto(s)
Sustitutos de la Leche/farmacología , Leche , Páncreas Exocrino/efectos de los fármacos , Páncreas Exocrino/metabolismo , Porcinos/crecimiento & desarrollo , Alimentación Animal/normas , Animales , Animales Lactantes , Peso Corporal/fisiología , Colecistoquinina/sangre , Dieta/veterinaria , Modelos Lineales , Jugo Pancreático/química , Porcinos/fisiología , Tripsina/sangre , Tripsina/metabolismo
16.
J Physiol Pharmacol ; 57 Suppl 6: 17-42, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17228085

RESUMEN

Orexin-A (OXA, hypocretin-1) and orexin-B (OXB, hypocretin-2) are peptides derived from the same 130 amino acid long precursor (prepro-orexin) that bind and activate two closely related orphan G protein-coupled receptors. Orexins and their receptors were first discovered in the rat brain, and soon after that in peripheral neural structures, including the vagal nerve and enteric nervous system, and in other structures involving the gastrointestinal tract diffuse neuroendocrine system, pancreas tissue, stomach and intestinal mucosa. Orexins and their receptors were also demonstrated in the testes, adrenals, kidneys, and placenta. This review is focused on central and enteric actions. Originally, orexins were considered to be neurotransmitters that centrally stimulate food intake in animals and humans, but it soon became evident that their action is broader due to activation of a large number of neuronal pathways involved in energy homeostasis, sleep-awake behavior, nociception reward seeking, food and drug addiction, as well as reproduction, cardiovascular and adrenal function. In the gastrointestinal tract, orexins have been found so far to affect gastrointestinal motility and gastric, intestinal and pancreatic secretions. The effects were observed following central (intraventricular) or local (intraluminal, intraarterial), but not peripheral (intravenous), administrations of orexins. Since the expression of orexins in the gastrointestinal tract is enhanced during fasting, and fasting reveals many of the orexin gastrointestinal effects, it seems probable that on the local level, orexins keep the gastrointestinal tract functions ready during fasting and play role in brain-gut axis control.


Asunto(s)
Tracto Gastrointestinal/fisiología , Péptidos y Proteínas de Señalización Intracelular/fisiología , Neuropéptidos/fisiología , Secuencia de Aminoácidos , Animales , Tracto Gastrointestinal/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Datos de Secuencia Molecular , Neuropéptidos/metabolismo , Receptores de Orexina , Orexinas , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/fisiología , Receptores de Neuropéptido/metabolismo , Receptores de Neuropéptido/fisiología
17.
J Physiol Pharmacol ; 57 Suppl 6: 43-54, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17228086

RESUMEN

Orexin-A and -B (OXA, OXB) are peptides involved in many gastrointestinal (GI) functions, including motility. Orexins, their precursors and receptors are present in the GI tract. The expression of orexins increases in the hypothalamus and gastrointestinal tract in response to fasting. We have examined the effect of OXA and OXB on GI motility in vitro in fed and fasted rats. The intestinal segments were mounted in chambers filled with Krebs solution. Isotonic contractions were measured in response to acetylcholine (10(-5) M), electric field stimulation (EFS), and orexins (10(-9)-10(-7) M) alone or in the presence of orexin-1 type receptor antagonist, SB- 334867 (10(-5) M), tetrodotoxin (TTX) 10(-6) M, or atropine (10(-5) M). Orexins caused a dose-dependent increase of intestinal segment contractions with a more pronounced effect of OXB over OXA. Fasting did not influence orexin-induced responses. Incubation with SB-334867 led to a marked decrease in orexin-induced contractions in OXA-treated segments, while those of OXB were not affected. Atropine diminished contractions only in fasted animals, while TTX led to a decreased response to orexins in both groups. The results show that OXB is predominant in inducing gut motility response, that the effect of orexins is not fully dependent on cholinergic and Na(+) transmissions, and that involvement of other transmitters is possible.


Asunto(s)
Ayuno/fisiología , Motilidad Gastrointestinal/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/farmacología , Yeyuno/efectos de los fármacos , Neuropéptidos/farmacología , Animales , Atropina/farmacología , Benzoxazoles/farmacología , Interacciones Farmacológicas , Motilidad Gastrointestinal/fisiología , Técnicas In Vitro , Yeyuno/fisiología , Masculino , Contracción Muscular/efectos de los fármacos , Naftiridinas , Orexinas , Distribución Aleatoria , Ratas , Ratas Wistar , Tetrodotoxina/farmacología , Urea/análogos & derivados , Urea/farmacología
18.
J Physiol Pharmacol ; 56 Suppl 3: 7-24, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16077193

RESUMEN

Apoptosis is a fundamental process in the development of the fast growing intestinal mucosa. Apoptotic cells are present along the whole length of the villi and in the crypts. The mechanisms involved in the induction of apoptosis in the gut mucosa are still unknown. Cytokines are believed to play a role in auto- and paracrine models because the cells are dying in so-called "packets" containing neighboring cells. In the rapidly developing gut of neonates, the apoptosis rate is transiently reduced in the first days of life, enhancing the growth of mucosa. Afterwards, apoptosis plays a role in the exchange of the enterocyte population, facilitating maturation of the mucosa. The presence of autophagic cells has been confirmed for the first time in the developing gut. Deprivation of growth factors during feeding artificial milk formula led to an increased apoptosis rate. Supplementation with leptin reduced cell apoptosis and increased the mitosis-to-apoptosis ratio. Autophagy was also diminished. The key to healthy gut mucosa growth in early life, especially in fast-growing animals, is colostrum, which supplies nutritional and defensive components together with supplementary growth factors, cytokines and hormones essential for growth and maturation of gut mucosa.


Asunto(s)
Apoptosis , Mucosa Intestinal/patología , Intestino Delgado/patología , Transducción de Señal , Animales , Animales Recién Nacidos , Autofagia , Calostro/metabolismo , Enterocitos/metabolismo , Enterocitos/patología , Humanos , Fórmulas Infantiles/metabolismo , Recién Nacido , Mucosa Intestinal/crecimiento & desarrollo , Mucosa Intestinal/metabolismo , Intestino Delgado/crecimiento & desarrollo , Intestino Delgado/metabolismo , Leptina/metabolismo , Microvellosidades/metabolismo , Microvellosidades/patología , Mitosis
19.
J Physiol Pharmacol ; 56 Suppl 3: 71-87, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16077196

RESUMEN

Modifications in the structure of gastrointestinal mucosa is often used to evaluate gut function for instance during the development or in response to particular food components. Scanning electron microscopy (SEM) gives a chance to observe the surface of the gut epithelium in three dimensions. However, this technique is seldom used due to technical difficulties. The present study attempted to investigate the intestinal mucosa structure changes in the postnatal pig using light and scanning electron microscopy technique. Experiments were carried out on sow reared piglets from birth until 38 days of age. Piglets were sacrificed at birth and at the 3(rd), 7(th), 21(st) and 38(th) day of life. The entire gastrointestinal tract was immediately harvested and the whole thickness tissue samples were taken from the duodenum, jejunum and ileum for optical and scanning electron microscopy. SEM analyses corroborated with histometry made by optical microscopy. Moreover, a number of shape modifications of the villi and its surface have been observed. The development changes in small intestine mucosa during the first 3 weeks were manifested in shape, size and density of villi. In conclusion, the structure of small intestinal mucosa undergoes profound structural changes. SEM gives a new dimension in the investigation of gut mucosa.


Asunto(s)
Mucosa Intestinal/ultraestructura , Intestino Delgado/ultraestructura , Microscopía Electrónica de Rastreo , Animales , Animales Recién Nacidos , Apoptosis , Duodeno/ultraestructura , Enterocitos/ultraestructura , Células Caliciformes/ultraestructura , Íleon/ultraestructura , Imagenología Tridimensional , Mucosa Intestinal/crecimiento & desarrollo , Intestino Delgado/crecimiento & desarrollo , Yeyuno/ultraestructura , Microvellosidades/ultraestructura , Porcinos
20.
Spine (Phila Pa 1976) ; 30(7): 769-73, 2005 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-15803079

RESUMEN

STUDY DESIGN: A retrospective analysis was performed. OBJECTIVES: To determine the oncological outcome of patients with nonmetastatic Ewing's sarcoma of the mobile spine treated with systemic multiagent chemotherapy combined with radiation therapy for definitive local control. SUMMARY OF BACKGROUND DATA: To our knowledge, there are no studies that evaluate the oncological outcome of patients with nonmetastatic Ewing's sarcoma of the mobile spine treated with systemic chemotherapy and radiation therapy for definitive local control. METHODS: Thirteen patients with nonmetastatic Ewing's sarcoma of the mobile spine were treated with high-dose multiagent chemotherapy combined with radiation therapy for definitive local control from 1971 to 2000 at a single institution. Patients were observed for a minimum of 2 years or until death. Neurological function, local recurrence, distant relapse, and treatment-related complications were evaluated. RESULTS: There were 8 females and 5 males with a mean age of 19 years (ranging from 7-26 years). The mean follow-up time was 65 months (median 28 months; ranging from 2 to 218 months). All patients presented with pain. Motor deficits were present in 6 patients. Ten patients had a decompressive laminectomy. Improved pain control, as determined by narcotic use, was noted in 12 (92%) patients. Ten patients maintained or improved motor function by at least 1 Frankel grade, while 3 had deterioration of motor function. The disease-free survival rate was 49% and 36% at 5 and 10 years. Five (38%) patients were free of disease at last follow-up. Seven patients developed metastatic disease. Three (23%) patients developed a local recurrence. One of these patients had paraplegia associated with the local recurrence. Five patients developed 8 treatment-related complications. Four of the 10 (40%) patients that had a laminectomy developed progressive kyphosis. Two of these patients also developed late-onset cauda equina syndrome along with the deformity. One of these patients also developed cardiomyopathy associated with adriamycin cardiotoxicity. One patient developed a nonhealing pressure ulcerover a prominent spinous process. CONCLUSIONS: The current study provides historical data on a relatively homogeneous group of patients withEwing's sarcoma of the mobile spine treated with multiagent chemotherapy combined with radiation therapy for definitive local control. Systemic chemotherapy combined with current spinal resection and reconstruction techniques may lead to improved oncological and clinical outcomes.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Radioterapia , Sarcoma de Ewing/terapia , Neoplasias de la Columna Vertebral/terapia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Niño , Terapia Combinada , Descompresión Quirúrgica/efectos adversos , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Laminectomía/efectos adversos , Imagen por Resonancia Magnética , Masculino , Recurrencia Local de Neoplasia , Radiografía , Radioterapia/efectos adversos , Estudios Retrospectivos , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/diagnóstico por imagen , Neoplasias de la Columna Vertebral/diagnóstico , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Neoplasias de la Columna Vertebral/radioterapia , Resultado del Tratamiento
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